This invention relates to chairs, and more particularly to an arrangement for mounting a chair back support member to the underside of a chair seat.
Typical chair construction involves mounting a chair seat and chair back to a chair control mechanism, which in turn is supported above the floor by a chair base. The chair control mechanism is mounted to a support column associated with the base, which typically is in the form of an adjustable height gas cylinder for varying the elevation of the seat above the floor. The chair back is typically mounted to the upper end of a chair back support. The chair back support defines a lower end which is mounted such that the chair back is spaced above the seat and located toward the rearward end of the seat. The lower end of the chair back support may be mounted to the underside of the seat, or mounted to the chair control mechanism. Mounting of the chair back support to the seat or the chair control mechanism may be a fixed-type mounting in which the position of the chair back relative to the seat is fixed, or such mounting may include provisions for altering the angle of the back relative to the seat.
Chair back supports are commonly in the form of a J-bar, which defines an upper end to which the chair back is mounted, and a lower end adapted for mounting either to the underside of the seat or to the chair control mechanism. J-bars are commonly formed of bent bar stock, and the width and thickness of the J-bar typically varies according to the chair design and different user or manufacturer requirements. These variations in the width and thickness of the J-bar present difficulties when the J-bar is to be mounted to the chair control mechanism. In the past, it has been known to provide chair control mechanisms with a different J-bar mounting area for each width and thickness of J-bar available. This requires separate tooling for each such J-bar mounting area and different part numbers for each version of the same chair control mechanism which has a differently configured J-bar mounting area.
It is an object of the present invention to provide a mounting arrangement for a chair back support member which is capable of accommodating chair back supports of varying dimensions. It is another object of the invention to provide such a mounting arrangement which is well suited for use in mounting differently configured chair back supports to a chair control mechanism. Yet another object of the invention is to provide such a mounting arrangement which entails relatively minor alterations in the configuration of a mounting area associated with a chair control mechanism while accommodating differently configured chair back support members. Yet another object of the invention is to provide such a mounting system which is relatively simple in its configuration and components and which is easily adapted to use with chair back support members of different configurations.
The invention generally contemplates a mounting system for a chair back support member, for mounting a chair back support member to a chair seat or to a chair control mechanism. The mounting system of the invention is capable of mounting chair back supports of varying width and thickness. In a preferred form, the mounting system is interconnected with the chair control mechanism, such that the chair control mechanism and mounting system are together secured to the underside of the seat.
In one form of the invention, the mounting system is provided on a receiver which is secured to seat support structure associated with the chair control mechanism. The receiver includes an opening through which the chair back mounting member extends, and an engagement arrangement located inwardly of the opening, for engaging the chair back support member with the receiver. The engagement arrangement may either be a fixed-type arrangement in which the position of the chair back is not adjustable relative to the seat, or an adjustable arrangement in which the position of the chair back relative to the seat can be adjusted. The invention contemplates positioning one of a series of inserts within the opening in the receiver, and each insert defines a passage configured to receive a chair back mounting member having a specific configuration. The passage in each insert is configured according to the specific dimensions of one type of chair back mounting member, such that each insert has a differently configured passage according to the number of different chair back mounting members which may be employed in connection with the chair control mechanism. In this manner, the same chair control mechanism and receiver is used for each available chair back mounting member, and it is only necessary to position the desired insert within the opening in the receiver according to the configuration of the chair back mounting member to be used for a particular chair.
In another form, the invention contemplates a mounting area for a chair back support member which includes a pair of spaced sidewalls together with an engagement wall which extends between the pair of spaced sidewalls. Inwardly extending protrusions are provided on each of the sidewalls. The sidewalls, engagement wall and protrusions are configured so as to define a mounting area adapted to receive the lower end of a chair back support member having a maximum width and thickness. When a chair back support member having a lesser width and/or thickness is to be used with the chair control mechanism, a set of inserts are engageable within the protrusions to alter the configuration of the mounting area to accommodate the lesser thickness and/or width of the chair back support member. Each set of inserts is specifically configured for a particular width and thickness of chair back support member which is adapted to be used in combination with the chair control mechanism. With this arrangement, the same basic structure of the chair control mechanism is employed, and the inserts are used as needed according to the configuration of the chair back mounting member to be used for a particular chair. The mounting area again includes an engagement arrangement for securing the chair back mounting member to the chair control mechanism, which may either be a fixed-position or adjustable engagement arrangement.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.